What Browser are you using?
What site gives this message?
Define "Other Site"
Safari is currently at version 8.0.2
P
"the certificate for this site is invalid" Since updating to Yosemite 10-9-5 "Safari" give me this message every time I goto another site. All the fixes I can find don't work.
Google doesn't have this problem.
Will the next update fix it??

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